Humidifier boiler



Sept. 8, 1953 E. W. BOTTU M HUMIDIFIER BOILER Filed March 16, 1949 IN VEN TOR.

EDWARD W. BQTTuM A TTORNEY Patented Sept. 8, 1953 HUMIDIFIER BOILEREdward W. Bottum, Detroit, Mich., assignor to Skuttle ManufacturingCompany,

Detroit,

Mich., a corporation of Michigan Application March 16, 1949, Serial No.81,809

Claims. 1

This invention relates to a vaporizing apparatus for discharging vaporinto a gaseous medium and more particularly, but not exclusively, to ahumidifier in which Water or other vapor may be discharged into an airmass in quantities controlled by variations in the calorific output of aheating unit.

It is well known that air heated by a conventional furnace, or otherheating unit, has a relatively low humidity which is both uncomfortableand unhealthy. Many humidifying devices for heating units have beenpreviously suggested and used. For the most part, the devices have beenincapable of providing the necessary degree of humidification for theair and also have been incapable of rapidly and suddenly changing inresponse to changes in the heating output of the heating unit. For thesereasons, the prior humidifying devices have proven unsatisfactory.

Most frequently the conventional humidifying apparatus employedconsisted of an open pan or receptacle of water positioned either withinthe heated rooms or within the air chambers of the furnace itself.Humidifiers of this type are not satisfactory for use under manyconditions. Due to the high heat of vaporization of water, substantialheat is removed from the surrounding air by this type of humidification.Various methods for increasing the water vaporization in water pans orreceptacles has been employed such, for example, as increasing theeffect of vaporization surface of the Water, by the use of absorbentfins or plates, or by increasing the temperature of the water in thereceptacle. While these methods have increased the vaporization rate,the increase has in some instances been in sufficient to provide thedesired amount of humidification; heat is still absorbed from thesurrounding air to evaporate the Water; and in addition, the amount ofhumidity supplied to the air cannot be accurately controlled tocompensate for sudden changes in the heat output of the furnace. In theprior humidifiers wherein the Water is heated, such as by heating coils,a substantial quantity of water must be kept in the receptacle at alltimes in surface contact with the heated air. For this reason the watercannot be heated or cooled quickly to suddenlychange the vaporizationrate and consequently compensate for sudden changes in the temperatureor1 volume of the heated air.

With the humidifying apparatus of the present invention, water. ismetered to a steam chamher in proportion to the evaporation rate withinthe chamber, which in' turn is in proportion to the heat of the gases inthe furnace flue. The apparatus includes a water reservoir positionedoutside the heated portion of the furnace, a heat transfer unitpositioned within a heated portion of the furnace, preferably within thefurnace flue, and one or more absorbent plates extending from the waterin the reservoir into a steam chamber provided in the heat transferunit. In operation, no liquid Water is present within the steam chamberexcept that which is present on the surface of the absorbent material.The rate of flow of water to the chamber is thus dependent solely uponthe rate of vaporization of the water from the surface of the absorbentplates. Any number of absorbent plates may be employed to provide asuflicient flow for maximum vaporization rates within the chamber.

The steam generated in the steam chamber is directed into the heated airby any suitable means. If desired, forced circulation may beemployedsuch as by the use of a centrifugal blower toforce the steam from thechamber into the heated room, or if desired, into the furnace hot airducts.

Prior humidifiers which are dependent upon currents of heated air toabsorb the moisture and carry it into the area to be heated, are of novalue in heating systems utilizing hot water or steam as the heatexchanging medium in radiators or the like located in the area to beheated. The efficiency of such heating svstems is well known but thedifficulties in providing suitable humidification in areas heatedthereby have reduced the demand for such heating systems.

It is therefore an object of the present invention to provide avaporizing apparatus which may be used with any type of heating systemto supply and discharge vapor into the air in an area to be heated incuantities necessary for maintaining a uniform and satisfactorypredetermined volumetric concentration of the va or which will varyautomatically with the heat output of the heating system.v

It is another object of this invention to provide a humidifyingapparatus which will supply water in vaporized state to heated andrelatively dry air and will automatically and quickly vary the watervapor output to the air in accordance with the heat output from thefurnace.

Still another object is to provide an apparatus which is sensitive tosmall variations in the heat output of the furnace whereby a relativelyconstant humidification of the air may be obtained.

Another object of the invention is to provide a humidifying apparatus inwhich only a small quantity of liquid water is present within the steamchamber on the surface of the absorbent plates in order that the steamoutput of the apparatus may vary rapidly with small temperaturevariations within the chambers.

Another object of this invention is to provide a humidifying apparatushavingsameansto force the flow; of .-water vapor fromi-the' steam:chamber into the relatively dry air of the area to be heated.

Other objects of this invention will appear'in the following descriptionand appendednclaims, reference being had to the. accompanying...drawingsforming a part of thespecificationwherein like reference charactersdesignate corresponding parts of the several views.

In the drawings:

Fig. 1 is a front elevation of the humidifying apparatus embodying thefeatures of the present .inventiornand .showing the water.chamber.in

section. .andalso showing a portion ..of.'..the cover plate broken-away.for .clarity:

(Fi 2 isa sectional view: taken substantial ly on the. line," 2-2.ofJFieu- 1; and

Fig. 3. isa. reduced fragmentary sectional view showing anmodification,of' the humidifying. ap- .paratus ,of .thepresentinvention.

Before. explaining thepresentlinvention" in "detailitisto beunderstoodthatlthe invention'is .not limitednin -its .iapplication to the details.of

construction and .arrangement .of ..parts .illus- .tratedinthe.accompanving. drawin s, ,since the .inventionds .capablesofptherembodiments and of being..practicedoncarried out. in various ways.

-Also it .is. to"- be .understood. ithatjthe. phraseology or terminolo yemployed;herein'isiorthegfiurposeof descriptioniandenohofllimitation.

.The. humidifyingsapparatus I I) -of. thepresent invention. is.shown.in,l=igs.-1 vand.;2 of ,thejdrawsings-in,assembledrelation withanlassembly plate .12 and anwater-..chamber..l 3 having a.-,standard.type float control-ILtherein. .The .humidifying apparatus 10 comprisesessentially the heattranstier-- unit. I.5 .having. a.-steam..chamber .16f therein, .awater reservoir, 1 I and. a plurality of .absorbents-plates I8 rextending .from .the .-water ['9 -in .the .reservoir .intothe -steam-. chamber .I 6 ..provided in the heat transfersunit.

1-As r shown .in. the drawings, ,a--.unitary hollow member forms both.;the rectan ular -.-heat sexchanger .-unit, includingi the: fins .20and .the soylindricalbody-portion.- 2 I of. the Nl'fitBIExBGSGHlOiI'.

The; hollow -member.,is formedof .a Anon-corrosive heat.conductingz-material suchaaaluminum and-is preferably of a castconstruction. .Oneend ofthefsteam chamben opens into thewater reservoir,butis positioned.-above..the .normal .level of the PWaterWith-insthe;reservoir. .Thewater. is carried bycapillary. action withinthe absorbentplates ts from. :the I reservoir I! into .the -steam --chamber. and;anyexcess .water .in .the. chamber such as by condensationpfthemater.vaporwill fiowbygravityback into therreserv-oir I I.

Theopemendof .the .body ;portion ,2 I of .the :reservoir I! is provided.withmpair. .of transverse iianges :22. .A- coverplate..23 encloses the.open -end-of thebody portion and is removablysecured thereto by-a-.pairofscrewsifi threadeddnto the transverse flanges -12.:Thecover-plate ,is-provided-with .an; annular .flangeliiwhich. seats onthe outer. periphery. .ofthe .body portion; 2 I. An annular. gasket26-is positioned withinthe flange 25=and seals the open-end. of.thewatenreservoir. An outlet port.-21 is formed in-a threaded ,boss 28located in the top of the body portion 2| and 4 communicates with thesteam chamber. Vapor is led from the outlet port 21 through the conduit21a which discharges into any desired area. The threaded boss 28 isprovided with a thread- 5 ed nut 29 which with the packing 29a providesa vapor tight connection with the conduit 21a. The water chamber isalso. provided with a downwardly depending water inlet port 30 having anopening in one end thereof connected with the conduit 3i extending fromthe water chamber I3. "The opposite end of the water inlet port and also'fithesheat exchanger unit I4 are each provided witha threaded plug 32.

iThe'a-bsorbentzplates I8 are generally L-shaped .15 ;;and-are supportedvertically within the steam chamber I and have the short arm portionsI80, .extendingzbelowithe liquid level line I9. The ,plates arepreferably formed of compressed glass fibers or'the like having a porousstructure providing a plurality of capillary spaces in which "the liquidmay riseby capillary attraction from the -reservoir I'l intothe-"chamber *IB. In-"op- -erat-ion" the liquid on thesurf ace oftheabsorbent plates 18 is evaporated by the heat given up by theheatconducting walls'ofthe heat exohanger and -is discharged into therelatively 'dry "air through the outlet port 21. -'Asshown in thedrawings,"-six'plates have been'found suitable for mo'st humidifyingpurposes. However, any numberof absorbent plates I8 may be employed in'the apparatusas desireddepending upon the liquid to be evaporated, theextent of dehydration' and thevolume of the'a-irto be'humidified.

The waterlevelin the waterreservoir is conitro'lle'd" and maintained bythe water'level in the water chamber, which in turnis 'controlled'by thefloat control mechanism I4. The latter -mechan-ism"-includes a plungervalve 33 for controlling the'fiow :of water into the water cham--"ber"and is operated'by the-float through the 'connectingarmflfiandthelink 36. 'The arm.

."flblY supported on the-'U-shaped'bracket 38 by the'thumb nut 39. Thebracket 38has an end portion-40 rigidlysecured to the adjacent innerwall *of" the water chamber.

.The" float. 3 4 'may be manually operated to open ".thetvalve '33bythefioat control arm ll. The latter issupported by thewater chambercover dtandds pivotally secured intermediate the ends .of "the-controliarm 4| to the angle bracket '43 mounted onthe cover.

:IIhe float control arm 4| is provided with a "handle portion .44extending through a longitudinal slotztherein'and the lower end 'ofthecontrolarm is twisted to. provide a transverse portion 45 whichisadapted to engage the float ;arm35 upon upward movement of the handleportion ofthe control arm. An overflow pipe 45 is also. providedinthewater chamber I3.

The assembly. plate. I2 is shown comprising a ,pair .of plates,..eachplate .of which has one end secure,d -.as.at .41 to the body portion 2!.The .other .end 48 voreach plate is..curved.inwardly .ltdconform to theexternal contour of. the metal -flue. .ofany. conventional. furnace.

A .modificationof the invention is shown in .Eig. .3-in.which acentrifugal fan. is mounted .on the end platelifl secured to the waterreservoir H. 'The centrifugal fan is driven through the shaft .5Lby themotor =5.Z;secured by any'suitable means onthe outside of the coverplate 50. .Thelatter is.,provided with'an annular air'inlet I .opening.53 in the low pressurearea "adjacent the axis of-the shaft.

With the present apparatus, the heat exchanger, preferably extendinginto the flue of the furnace, is heated by the combustion gases withinthe flue in proportion to the temperature of the combustion gases. Theheat generated within the vaporization chamber therein vaporizes theliquid on the surface of the absorbent plates and discharges the vaporinto the area to be heated in quantities necessary for maintaining auniform and satisfactory predetermined volumetric concentration of thevapor. The quantity of vapor generated in the vaporization chamber willthus vary automatically with the heat output of the heating system.

The vaporizing chamber is positioned above and opens into the waterreservoir whereby any excess liquid present within the vaporizingchamber, such as due to condensation, will immediately return by gravityflow to the reservoir. For this reason, the only liquid present withinthe chamber is the small amount present within the absorbent plates andon the surfaces thereof so that the apparatus will operate quickly tovary the vapor output to the air in accordance with the heat output ofthe furnace and is sensitive to small variations in the heat outputthereof.

The vapor generated in the vaporization chamber is dis-charged intorelatively dry air through a discharge port in the vaporization chamberand thence through any suitable tubing. While the water vapor may beinjected into the warm air ducts of a hot air system, the apparatus alsois particularly adapted to discharge the vapor through a tubular conduitdirectly into the heated area or heated rooms. The apparatus istherefore well adapted to provide sensitive and efficient humidificaticnfor an area heated by a. hot water or steam heating system.

It is to be understood that any desired type of liquid may be employedto provide the vapors which are to be diffused. For example, a liquidtherapeutic agent, such for example as a glycol may be used, either withor without water and vaporized by the device of the present invention toprovide a vapor which may be diflused throughout any desired area.

If water is used as the liquid, steam is generated and is used as thehumidifying agent. It

has been found also that a portion of the steam generated may bedischarged into the furnace stack to aid in cutting down the amount ofsmoke discharged through the flue.

Having thus described my invention, I claim:

1. A vaporizing apparatus for maintaining a desired vapor content in agaseous medium, comprising a heat exchanger adapted to extend within aheated portion of a heating unit and having a closed vaporizing chambertherein disposed Within the heated portion of the heating unit andprovided with a vapor discharge port communieating with the gaseousmedium exteriorly of the heated portion of the heating unit, a liquidreservoir mounted exteriorly of the heated portion of the heating unitand adapted to contain a volatile liquid, an absorbent liquid meteringmember having a portion immersed in the liquid in said reservoir andanother portion extending into said vaporizing chamber to meter theliquid from said reservoir at a rate substantially proportional to therate of evaporation of the liquid from the portion of said memberextending into the vaporizing chamber of said heat exchanger, and meansto prevent the accumulation of liquid in said vaporizing chamber inexcess of the liquid retained by said absorbent metering member.

vapor discharge port communicating with the atmosphere exteriorly of theheated portion of the heating unit, a liquid reservoir mounted ontheoutside of said heated portion of the heating unit and adapted tocontain a quantity of liquid water, an absorbent liquid transfer memberhaving a portion immersed in the water in said reservoir and also havinga portion extending into said vaporizing chamber, said member meteringthe water from said reservoir at a rate substantially proportional tothe rate of vaporization of water within said heat exchanger, and meansto prevent the accumulation of liquid water in said vaporizing chamberin excess of the liquid water retained by said absorbent liquid transfermember.

3. A humidifying apparatus in accordance with claim 2 and furthercharacterized in that said absorbent member comprises plates having astructure including a plurality of capillary spaces whereby the water ismetered to said chamber by capillary attraction through said plates at arate substantially proportional to the rate of vapo'rization of waterwithin said heat exchanger.

4. A humidifying apparatus for maintaining a desired moisture content inthe atmosphere of an enclosed space, comprising a heat exchanger adaptedto extend into a flue of a furnace and having a steam chamber thereindisposed within the flue and provided with a steam discharge port tocommunicate with the atmosphere exteriorly of the flue, a waterreservoir mounted on the outside of said flue and adapted to contain aquantity of water, an absorbent plate having a portion adapted to beimmersed in the water in said reservoir and also having a portionextending into said chamber, means for maintaining the water within saidreservoir at a constant level, said plate metering the water from saidreservoir at a rate substantially proportional to the rate ofevaporation within said heat exchanger, and means to prevent theaccumulation of liquid water in said steam chamber in excess of theliquid water retained by said absorbent plate.

5. A humidifying apparatus for maintaining a desired moisture content inthe atmosphere of an enclosed space, comprising a heat exchanger adaptedto extend into a flue of a furnace and having a steam chamber thereindisposed within the flue and provided with a steam discharge portcommunicating with the atmosphere exteriorly of the flue, a waterreservoir mounted onthe outside of said flue and positioned below saidsteam chamber, and a Water absorbent plate having a portion immersed inthe water in said reservoir and also having a portion extending intosaid chamber, said plate metering the water from said reservoir at arate substantially proportional to the rate of vaporization of waterwithin said heat exchanger, said heat exchanger having an opening at thebottom of said steam chamber and communicating with said reservoir, thebottom of said heat exchanger being above the level of the water in saidreservoir whereby condensation within said steam chamber will return bygravity flow to said reservoir.

ifihethumidifying' apparatus: for maintainingra edesired :nioisture:content: in:the:atmosphere of ean z-enclosedrspace comprising a .hollowmember cof;:heattconducting1 material having :an openingzatoonewnd'thereof, the closedendportion of said :ho'llow:memberzforming a steam chamber @and -=being=radapted ton-extend intoa'heated portion cofriafheating unitaa cover-plate for closingthenpening end of :said hollow member'and cooperatfingztherewithz-toprovide a water reservoirposiitionednexteriorly:of the heated-portion.of the sheating unit below said steamchamber where- "ibywaterfcondensation within the latter :will return :by:=;gravity now tothe reservoir and an :absorbentgplate positioned withinsaid hollow .mem-:ber zandsextendingirom said steam chamber to 1saidrreservoir =wherebywater within the latter is meteredtozthe steam chamber in; proportionttoithe iratevof vaporization within said chamber,

z-said hollow member having "a steam discharge sport adapted" to.communicate with the eatmosrphere.

7. 2A. humidi fying apparatus for maintaining-a desired moisture contentin the atmosphere oil-an -:enclosed space .comprisinga hollow member ofzheat conducting material having an opening'at -one'end thereof,-theclosed end portion ofsaid hollow member forming asteam chamber havingexternal heat conducting fins and being adapted -toiex-terrd into-aheated portion of a, heating unit, -a.-cover,plate'for closing the openend of-said holt.low member and cooperating therewith to provide a waterreservoir 'positioned'exteriorly of .the heated :portion of the heatingunit and be- -low-said steam chamber, means for maintaining the-water:level inesaid reservoir below thebot- ,tom of saidsteam chamber wherebywatercondensation-within the latter-will return bygravity .-flow-.to.thereservoir'and an absorbent plategpositioned within said -hollow memberand extend- .ing from-saidsteam chamber to said reservoir whereby waterwithin the latter ismetered to the steam'chamber in proportion to therate ofva- .por-ization "within 'said chamber, said hollow member havinga steam discharge port adapted .to communicate with the atmosphere.

.8. A'humidifying apparatus for'maintaininga desiredrmoisture content inthe atmosphere of .an enclosedspace comprising a hollow member of heat.conductingmaterialhaving an opening at one end-thereof, theclosedeendportionof said vhollowlmember l-forming 1a steam chamber and beingadapted to extend into a heated portion .of 1 a heating unit-acoverplate ior'closing'theopen end of said hollow member and cooperating"therewith tozprovideawater reservoir positioned ,exteriorly of theheated portion of the heating .unit and'below said steamchamben-means to,maintain the water-level in-said reservoir below .thebottom-of saidsteam chamber whereby .water condensation within the latter -will.return by qgravityfiow to the reservoirend an absorbent sL-shapedplatepositioned within said hollow niember,-.- one. endof" said L-shapedplate' extendingeinto said'steam chamber and the otherrend thereofextending into thewater within said reservoir whereby water within thelatter is me- .tered-to the steam chamber in proportion tothe .rate -ofvaporization within said chamber, said .hollow -member. having 1 a steamdischarge port :adapted to communicate withthe atmosphere.

.9. Ahumidiiying apparatus: for maintaininga desired moisture -.contentin .the 7 atmosphere of an enclosed-space comprising alhollow member"ofheatcondu-cting-material having an opening at one 'endthereoi-theclosed end portion of said'hollowtmember forming a steam chamber :andbeing adapted to extend 1 into a heated portionwf-a-heat-ing unit,acover plate for closing "the :open i end :of said hollow 1 member andcooperating therewith to provide a water. reservoir positioned:exteriorly 1 of :the heated :portion 101? the heating: unit and: belowsaidsteam chamber,

zmeanseto ma-intain the water levelin said reservoirrbelowz the bottomof saidsteam chamber, a :plurality of :qfilates eeach positionedwithinsaid 11 member and extending from said steam :chamber to saidreservoineach of saidplates 20:-

Hillary's-spaces wherebyithe water within the :reserhaving Iastru-ctureincluding a plurality of-capron is .metered by capillaryattraction ,-tothe steamwhamberin; proportion tothe rate of vaporization -within :saidchamber, said .hollow member"- having a: steam dischargeport adapted.toicommunicate with the atmosphere, andmeans to prevent theaccumulation of liquid water-in saidsteam chamber in excess of theliquidwater :retained bysaidplates and to'permit the --return of-anywater-condensation by gravity flow to said'reservoir.

10. A- vaporizing apparatus for maintaining a :desired-vaporcontent in agaseous medium, comprising a heat exchanger having a closed vaporizingchamber :adapted to bezplaced in heat =exchange-relation with a :heatedportion of a :heatingnnid-said vaporizing chamber communi- =cating withthe gaseous mediumexteriorly of the heated portion'of theheatingunit,'-a liquid .reservoirwmounted out'of heat exchange relation withthe-heated: portion ofthe heating unit and adapted-to containta volatileliquid, an absorbent liquid-metering member having a portion im- .mersedin the liquid in saidreservoir and another portion extending into saidvaporizing chamber to meterthe liquid from said reservoir at a ratesubstantially proportional tothe rate of vaporization of the'liquid fromtheportion of said chamber extending into the vaporizing chamber of.said heat-exchanger, and-means to prevent theaccumulation of liquid insaidvaporizingsehamber iii-excess of the liquid retained by saidabsorbent liquid metering member.

EDWARD W. BOTTUM.

References Cited in the file of this patent UNITED STATES'PATENTS NumberName Date 1,058,808 Thilges Apr. 15, 1913 1,158,553 Phelps Nov. 2, 19151,817,357 Fisher Aug. 4, 1931 "1,907,104 Hall May'2, '1933 2,032,553Spoelstra Mar. 3, 1936 2,113,024 Ireland Apr. 5, 1938 2,133,599 TurneyOct. 18, 1938 2,171,691 Geisler Sept. 5, 1939 2,427,531 Kuenhold Sept.16,1947

